1. Technical Field
The present invention relates to a charged particle beam irradiation device that irradiates a body to be irradiated with a charged particle beam.
2. Description of the Related Art
In the related art, a charged particle beam irradiation device disclosed in the related art is known as the charged particle beam irradiation device used for radiation therapy. The related art describes a particle beam treatment device that scans a charged particle beam by a scanning method and irradiates a body to be irradiated, such as a part of body with cancer, with the beam and that includes an inert gas chamber that is provided on a path of the charged particle beam, an integral gas supply pipe that supplies inert gas into the inert gas chamber, and a control device that controls the amount of gas supply of a gas supply pipe based on the difference between the internal and external pressures of the inert gas chamber.
In the aforementioned particle beam treatment device, isolating films are provided at an inlet and an outlet of the inert gas chamber to secure airtightness, and inert gas is supplied into the inert gas chamber to prevent damage of the isolating films by the difference between the internal and external pressures. Also, by arranging this inert gas chamber on the path of the charged particle beam, scattering of the charged particle beam under the influence of air is avoided and thus, irradiation position accuracy is improved.